The skull is composed of distinct bony plates that come together at joints called sutures that allow little or no movement, especially in adults. The joints between teeth and their sockets, called gomphoses, also allow very little movement.Continue Reading
At and before birth, the human skull, or cranium, is composed of several distinct bones that are held together with fibrous bands of tissue called cranial sutures. These bands allow the cranium to deform during childbirth with minimal risk of injury to either the child's brain or the mother. They also permit the cranium and the brain within it to continue growing after birth. As children grow out of infancy and the cranium approaches its adult size, these bands gradually turn into bone, and several of the bones fuse together. Even in adulthood, the seams between some cranial bones typically remain, with the bones being interlocked in a fashion that permits little or no movement.
Teeth are not technically bone, but the connection between teeth and their sockets is also described as a joint. While some slight movement occurs when chewing and when braces adjust the positions of teeth, this is negligible in comparison with more typical movable joints. These joints, called gomphoses, are another example of immovable joints
All joints in the skull are immovable except the temporomandibular joints, which allow the lower jaw to move up and down.Learn more about Human Anatomy
Injury during birth, head trauma, vitamin A toxicity, separated or malformed sutures, application of pressure, or rare congenital conditions can cause indentations in the skull, according to Healthline. When one of the skull's bones cracks, the depressed skull fracture sometimes dents inward, according to Drugs.com.Full Answer >
The sinus, or nasal cavity, serves to lighten the skull, to produce mucus, to warm and moisturize air breathed in through the nose and to serve as a chamber in which speech resonates. The sinus cavity is made up of four pairs of sinuses.Full Answer >
There are a total of four hollow sinus cavities in the human head, which are all located in the skull, according to WebMD. The four distinct parts that make up the sinus cavities in the skull are the sphenoid, maxillary, ethmoid and frontal sinuses. All of these sinuses contain pink, soft tissue and are connected to one another to form a single system.Full Answer >
Duke Magazine notes that the bones in the skull continue to grow as people age. The forehead tends to move forward while the cheekbones move slightly backwards, causing subtle changes to the human face. Because the facial bones tilt forward as people age, it causes sagging of the soft tissues.Full Answer >